Continuous-flow attachment for soft-cream freezers and method employing the same



March 12, 1957 STALKUP 2,74 ,565

CONTINUOUS-FLOP} ATTACHMENT FOR SOFT-CREAM FREEZERS AND METHOD EMPLOYING THE SAME :2 Sheets-Sheet 1 Filed Aug. 21, 1952 nulll lllllll IN V EN TORI Otis M. Stalkup BY A T TOR/VE Y.

March 12, 1957 STALKUP 2,784,565

CONTINUOUS-FLOW ATTACHMENT FOR SOFT-CREAM FREEZERS AND METHOD EMPLOYING THE SAME Filed Aug. 21, 1952 2 SheetS -Sheet 2 V INVENTO'R. 1 l fqi 4Z- Otis M. Stalkup ATTORNE CONTINUOUSvFLOW ATTACHMENT FOR SOFT- CREAM FREEZERS AND METHOD EMPLOYING THE SAME Otis M. Stalkup, Redondo Beach, Calif.

APPlication August 21, 1952, Serial No. 305,545

Claims. (Cl. 62--114) This invention relates to a continuous-flow attachment for soft-cream freezers and method employing the same. More particularly it relates to a conduit, controlled by a two-way, three-position dispensing valve, for recirculating soft cream from the dispensing end to the intake end of a conventional continuous-operation freezer, and provided with a thermostatically controlled electric heater for liquifying the cream to keep it smooth (i. e., free of ice crystals).

Soft-cream freezers of the prior art cannot maintain that quantity of the cream lying in the dispensing valve at the proper temperature, due to absorption of heat from the ambient air. The cream at or below the valve tends to completely liquify, and that between the valve and the freezer proper becomes too soft. This requires the drawing off of an appreciable quantity, especially when it has been some time since a last customer was served. This repeatedly drawn-off quantity is either wasted or is caught in an open receptacle where it is very likely to sour and/ or become contaminated by air-borne or insect-carried germs. The present invention not only prevents waste and contamination of the cream at the valve, but maintains the entire contents of the freezer at the desired consistency and homogeneity.

In the drawings, which disclose a preferred embodiment of the invention and in which like reference characters designate the same parts throughout the several views:

Fig. 1 is a plan view partly in section of a typical installation of my attachment on a conventional freezer.

Fig. 2 is an elevational view, partly in section, of the disclosure of Fig. 1.

Fig. 3 is an enlarged detailed elevational view of the heater, partly in longitudinal section.

Fig. 4 is a perspective View partly in section of the dispensing and recirculating valve.

Fig. 5 is a schematic elevation in axial section of the valve in dispensing position.

Fig. 6 is a schematic elevation in axial section of the valve in closed or off position.

Fig. 7 is a schematic elevation in axial section of the valve in its recirculation position.

With reference now to the drawings, the numeral 1 designates the metallic cylinder of a conventional freezer, having front and rear end plates 3 and 5. Cylinder 1 is refrigerated by a surrounding chamber or coils which is or are covered by an insulating jacket (all not shown) in conventional manners.

The rear wall 5 is provided with an inlet nipple 7 through which both the fresh frozen mix and the recirculated cream are introduced into the freezer. Nipple 7 is connected with a T 9 which in turn is connected to a sleeve 11 of transparent plastic material, such as tenite. Sleeve 11 is joined to an elbow 13 which connects the inlet nipple to the recirculation conduit generally designated as 15 and later to be described. Fresh mix is introduced, as by a funnel (not shown), into input pipe 17 connected to T 9 by an elbow 18.

nited States Patent 0 Patented Mar. 12, 1957 Freezer cylinder 1 is provided internally with a conventional rotating dasher 19. Dasher 19 comprises an axial hub 21 carrying the usual scraper blades 23 which are axially pitched so as to simultaneously propel the mix forwardly in the cylinder, churn the mix, and scrape frozen mix from the cylinder walls, all in well-known manner. It is preferable that the mix-moving blade should be of greater area, as at 23', at the front end of the freezer so as to increase the pressure relied upon for extruding the frozen cream, for use or for recirculation, through outlet sleeve 25.

Outlet sleeve 25 is connected by a union 27 to the valve inlet tube 29. Tube 29 carries a vertical valve body 31, which has a cylindrical bore at right angles to and intersecting that of the valve-inlet tube 29. Snugly but rotatably received in the bore of valve body 31 is the valve tube 33. Valve tube 33 is held against downward displacement by any suitable means, such as a pin or flange (not shown) or by the handle 35 resting on the top edge of valve body 31, as shown in Figs. 2 and 4. The upper end of valve body 33 is connected by a rotating-joint uni-on 36 to the upwardly extending portion of the recirculating conduit 15.

Valve tube 33 has two diametrically opposite ports 37 and 39 for communicating respectively with the dispensing nozzle and the recirculating end of the valve tube 33. Diagonally across and blocking the vertical bore in valve tube 33 is a baffie plate 41 which directs the cream downwardly for dispensing in the Fig. 5 position, or upwardly for recirculation in the Fig. 7 position. Fig. 5 discloses the intermediate position in which no flow occurs, since neither port is in registry with the bore of inlet tube 29. While the disclosure illustrates of rotation in its operation, with the off position midway between, it is obvious that lesser amounts of turning could be designed into the device by placing the ports close together (but still separated by the baffie). Also the position of the handle in Fig. 1 (-a convenient starting position for a right-handed person) could be either the dispense, the off, or the recirculate positions; and positions forwardly and rearwardly thereof could be any of the remaining operative positions, as desired.

The off and dispense positions are employed as with apparatus now in widespread use. However, with the disclosed attachment, when the soft cream is not being dispensed fast enough to prevent undesirable softening or melting of the cream in the valve portion of the freezer, the handle can be rotated to the new recirculation position to return the softer cream to the input end of the freezer and thus insure that all of the mix will be at desired consistency in each part of the apparatus at all times.

The recirculation conduit 15 comprises a main tube section 43 inserted between T 13 and valve 31. It also preferably includes a transparent plastic (or glass) section 44 for observation of its contents.

Around the outer surface of conduit section 43 there is placed a heating means 45 formed, for example, by an electric resistance heater 46, embedded in an insulating mass 47. Heater 45 is preferably provided with a thermostatic switch 49 connected in series therewith. Switch 49 can be made adjustable, as 'by a control 51, but it need not be made adjustable since it could be set for a temperature just high enough for melting of ice crystals to insure a smooth product. While the thermostatic switch may be of any conventional construction, it has been illustrated as comprising an elongated bulb 53 embedded in the insulating mass 47 of heater 45. Bulb 53 could lie between the conduit 43 and the heater 46, if desired. Bulb 53 is connected by capillary tube 55 to the bellows 56, which operates switch arm 57 responsively to the a A- A W temperature of the heater 45, in known manner. Knob 51 adjusts switch arm 59 to vary the temperatures at which the switch contacts carried by arms 57 and 59 make and break the heating circuit.

While I have disclosed a preferred illustrative embodiment of my invention, it is to be understood that many changes could be made in the size, shape, composition and arrangement of the parts without departing from the spirit of the invention defined by the subjoincd claims.

Having thus described my invention What 1 claim as new and desire to secure by Letters Patent of the United States is:

1. In a continueus-operation soft-cream freezer having an inlet and an outlet end, agitator means for churning the mix and forcing it toward said outlet end, and a dispensing conduit including a multiple-position manual valve connected to said outlet end, the improvement comprising a recirculation conduit connecting the outlet end of said freeze-r to the inlet end thereof so as to continuously or intermittently return the colder or more crystallized cream from the outlet end to the inlet end of the freezer to improve the homogeneity of the product; and heating means in said recirculation conduit in good heat exchange relation thereto whereby ice crystals in the cream will be melted to improve smoothness and fluidity of the product.

2. Apparatus according to claim 1 and in which said heating means includes a thermostatic device for preventing heating of the product much above the optimum temperature for desired smoothness and fluidity.

3. Apparatus according to claim 1 and in which said heating means includes at least two sleeve sections of poor heat-conductive material, one on each side of the heating means.

4. In a continuous-operation soft-cream freezer having an inlet and an outlet end, agitator means for churning the mix and forcing it toward said outlet end, and a dispensing conduit including a multiple-position manual valve connected to said outlet end, the improvement comprising a recirculation conduit connecting the outlet end of said freezer to the inlet end thereof so as to continuously or intermittently return the colder or more crystallized cream from the outlet end to the inlet end of the freezer to improve the homogeneity of the product; heating means in said recirculation conduit in good heat exchange relation thereto; and said recirculating conduit including at least one wall section of transparent material, whereby presence or flow of cream therein can be observed.

5. Apparatus according to claim 4 and in which said wall section is a sleeve of transparent plastic.

References Cited in the file of this patent UNITED STATES PATENTS 

